US Patent 10,870,676: DMD Exon-53 Antisense Patent Scope, Exclusivity, and Competitive Landscape

US Patent No. 10,870,676 is a Nippon Shinyaku patent directed to treating Duchenne muscular dystrophy with an antisense oligomer that binds a defined 21-nucleotide region of exon 53 in dystrophin pre-mRNA. The patent is closely aligned with viltolarsen, marketed in the United States as Viltepso. Its strongest protection is the sequence-specific method-of-treatment claim covering exon-53 skipping, with dependent claims adding oligonucleotide chemistry, morpholino and phosphorodiamidate morpholino oligomer structures, 5'-end groups, and intravenous administration.

The patent does not claim every exon-53 therapy. Its scope depends on the accused product containing an antisense sequence complementary to the specified nucleotides in the disclosed exon-53 sequence. A product targeting a different exon-53 region, using a noncomplementary mechanism, or treating DMD without the claimed sequence would fall outside the literal scope of claim 1.

What does US Patent 10,870,676 cover?

The patent covers methods of treating DMD by administering an antisense oligomer complementary to nucleotides 36 through 56, counted from the 5' end of exon 53 in human dystrophin pre-mRNA corresponding to SEQ ID NO: 1.

The independent claims are:

Claim	Covered subject matter	Principal limitation
1	Method of treating DMD	Administering the claimed antisense oligomer
2	Method of treating DMD using a pharmaceutical composition	Composition must contain the claimed antisense oligomer as active ingredient

Claims 1 and 2 are alternative independent method claims. Claim 1 focuses on administration of the oligomer or its pharmaceutically acceptable salt or hydrate. Claim 2 focuses on administration of a pharmaceutical composition containing the oligomer.

The patent does not require a particular DMD mutation, patient age, dose, treatment duration, dystrophin-restoration threshold, or clinical response. Those omissions broaden the method claims, subject to the sequence and treatment limitations.

What sequence does the patent target?

The claimed antisense oligomer must be complementary to the sequence consisting of nucleotides 36 through 56 of exon 53. The claim also requires that exon 53 correspond to SEQ ID NO: 1.

This creates two distinct claim elements:

The target window is fixed by position, from nucleotide 36 through nucleotide 56.
The underlying exon-53 sequence is fixed by the patent's sequence listing.

A sequence that binds a nearby region of exon 53 may not satisfy the claim if it does not consist of a sequence complementary to the specified 36th-to-56th nucleotide segment. The claim language is materially narrower than a generic claim to exon-53 skipping.

Does the claim require viltolarsen specifically?

Claim 1 does not expressly recite the name viltolarsen, a product code, a chemical formula, a backbone sequence by alphanumeric identifier, or a particular morpholino structure. It instead defines the oligomer functionally and sequence-wise.

That structure can capture viltolarsen if its antisense sequence is complementary to the claimed exon-53 region. It can also capture other oligomers with the same target sequence if they are administered for DMD treatment and otherwise satisfy the claim.

The independent claim therefore has product-neutral wording, but the sequence limitation remains central. A competing PMO with the same target sequence would face a substantial infringement risk even if it used a different terminal group or salt form.

How do the dependent claims narrow the patent?

Claims 3 through 10 depend from claim 1. Claims 11 through 18 repeat substantially the same limitations through claim 2.

Claims	Limitation	Commercial significance
3, 11	Antisense oligomer is an oligonucleotide	Captures conventional nucleotide-based implementations
4, 12	Modified sugar or phosphate-binding region	Covers chemically stabilized oligonucleotides
5, 13	Specified 2'-substituted ribose groups	Broad chemical modification category
6, 14	Phosphorothioate, phosphorodithioate, alkylphosphonate, phosphoramidate, or boranophosphate bonds	Covers multiple backbone chemistries
7, 15	Morpholino oligomer	Covers morpholino architecture
8, 16	Phosphorodiamidate morpholino oligomer, or PMO	Directly relevant to viltolarsen
9, 17	Specified 5'-terminal chemical groups	Narrows PMO protection to disclosed end-group structures
10, 18	Intravenous administration	Relevant to the approved Viltepso route

The PMO claims are commercially important because viltolarsen is a phosphorodiamidate morpholino oligomer administered intravenously. The broadest practical infringement theory is likely claim 1 or claim 2. Claims 8, 9, 16 and 17 provide narrower fallback positions directed to the product's PMO structure and terminal chemistry.

The supplied claim text does not reproduce chemical formulae (1) through (3) in claims 9 and 17. Their precise scope cannot be determined from the text alone. They should be read against the issued patent drawings and specification.

What is the relationship between US 10,870,676 and Viltepso?

Viltepso is viltolarsen, an antisense oligonucleotide approved by the FDA in August 2020 under the accelerated approval pathway for DMD patients with a confirmed mutation amenable to exon-53 skipping.[2]

The product is designed to bind dystrophin pre-mRNA and induce skipping of exon 53. The resulting dystrophin transcript can restore the reading frame in certain DMD mutations. The approved product is administered by intravenous infusion at a weight-based dose.

Product	Active modality	Exon target	Sponsor or manufacturer	FDA status
Viltepso	PMO antisense oligomer	53	NS Pharma/Nippon Shinyaku	Accelerated approval, 2020
Exondys 51	PMO antisense oligomer	51	Sarepta Therapeutics	Accelerated approval, 2016
Vyondys 53	PMO antisense oligomer	53	Sarepta Therapeutics	Accelerated approval, 2019
Amondys 45	PMO antisense oligomer	45	Sarepta Therapeutics	Accelerated approval, 2021
Elevidys	AAV micro-dystrophin gene therapy	Not exon-specific	Sarepta Therapeutics	FDA approval, 2023

Vyondys 53 is the principal direct commercial comparator because it also targets exon 53. Its existence does not by itself establish infringement. The relevant question is whether its antisense sequence is complementary to the exact 36th-to-56th nucleotide segment recited in US 10,870,676.

How strong is the patent estate for exon-53 DMD treatment?

US 10,870,676 has meaningful strength against products using the claimed target sequence and PMO chemistry. Its principal strengths are:

A defined exon-53 sequence rather than a broad disease-treatment concept.
Method claims that do not require a specific DMD mutation.
Coverage of salts and hydrates.
Direct dependent-claim coverage of morpholino and PMO structures.
Intravenous-administration claims consistent with the approved product.
Potential application to both the active ingredient and its clinical use.

Its principal weaknesses are:

The claims are limited to one exon-53 target window.
A competing product using a different exon-53 binding site may avoid literal infringement.
Method claims require proof that the accused product is administered to treat DMD.
The patent does not independently claim every formulation, manufacturing process, dosing regimen, or biomarker strategy.
Claims 9 and 17 depend on chemical structures not reproduced in the supplied record.
Antisense sequence and chemistry claims may face written-description, enablement, anticipation, obviousness, or claim-construction challenges depending on the asserted claim and prosecution history.

The patent is stronger as a blocking right against a copy or close sequence-based substitute than as a platform patent covering all exon-53 skipping products.

When does US 10,870,676 expire?

The patent's nominal term is tied to the earliest effective US or international filing date in its priority chain. Public patent records associate the family with a 2013 priority period. On that basis, the ordinary 20-year patent term would extend into approximately 2033 or 2034, before any adjustment.

Exclusivity right	Approximate endpoint	Effect
US 10,870,676 patent term	Approximately 2033-2034, subject to official term calculation	Potential injunction or damages exposure for infringing products
Viltepso orphan-drug exclusivity	Approximately August 2027	FDA approval block for the same orphan indication, subject to statutory exceptions
Pediatric exclusivity	Potential additional six months if awarded	Extends applicable regulatory exclusivity, not the patent term

The exact expiration date must be determined from the USPTO patent-term data, including patent-term adjustment, terminal disclaimers, and any applicable patent-term extension. Orphan exclusivity and patent protection are separate. FDA orphan exclusivity can block approval of a competing product even after a patent expires, while patent rights can continue after orphan exclusivity ends.[1,3]

What is the Orange Book status of US 10,870,676?

Viltepso is an FDA-approved small-molecule or chemically synthesized drug product, and its relevant patent information may be listed in the FDA Orange Book if submitted and accepted under FDA listing rules. Orange Book listing determines whether an ANDA applicant must make a Paragraph I, II, III or IV certification for a listed patent.

For an ANDA applicant seeking to copy viltolarsen:

Paragraph I applies if no patent information is listed.
Paragraph II applies if the listed patent has expired.
Paragraph III applies if the applicant accepts delayed launch until patent expiration.
Paragraph IV applies if the applicant asserts that the patent is invalid, unenforceable, or not infringed.

A Paragraph IV certification would create litigation risk under the Hatch-Waxman framework if the NDA holder files suit within the statutory period. A timely infringement action generally can trigger a 30-month stay of FDA approval, subject to statutory exceptions and court or FDA action.[4]

The relevant patent question is not whether an ANDA product treats exon-53 DMD generally. It is whether the proposed product and labeled use would fall within a listed method claim. FDA patent-listing practices and the Orange Book use-code statement also affect the practical value of the method claims.

Are there Paragraph IV challenges to viltolarsen?

A confirmed Paragraph IV challenge cannot be established from the supplied patent and claim text. No specific ANDA applicant, Paragraph IV notice, or federal complaint is identified in the record provided.

The commercial entry barrier is nevertheless high. A generic applicant would need to address:

The sequence identity of the proposed antisense oligomer.
The PMO or alternative backbone chemistry.
The labeled DMD indication and exon-53 patient population.
The patent's Orange Book listing and use code.
Orphan-drug exclusivity.
FDA requirements for demonstrating pharmaceutical equivalence, quality, and clinical substitutability for an antisense oligomer.

A generic product using the same target sequence and PMO architecture would have limited design-around flexibility. A product using a different exon-53 target sequence could reduce literal infringement risk but would require its own clinical and regulatory development program.

What formulation and manufacturing rights are protected?

The claims supplied here are method claims. They do not expressly claim:

A specific vial concentration.
A buffer or excipient system.
A particular infusion volume.
A manufacturing process.
A purification step.
A polymorph.
A particle-size distribution.
A dosing schedule.
A pharmacokinetic profile.

The patent does cover pharmaceutical compositions through claim 2 and claims 11 through 18, but the composition is protected only as part of a method of treating DMD. This is narrower than a composition-of-matter claim covering the formulation independent of use.

Manufacturing freedom-to-operate therefore requires review of separate patent families covering PMO synthesis, terminal-group chemistry, purification, formulation, sterile filling, and analytical controls. US 10,870,676 alone should not be treated as a complete manufacturing barrier.

What patent litigation and settlement risks affect exon-53 DMD products?

Potential disputes fall into four categories:

Dispute	Likely legal issue
Copy of viltolarsen sequence	Literal infringement of claims 1 or 2
Alternative exon-53 sequence	Claim construction, equivalents, and noninfringement
PMO competitor	Scope of claims 7-9 and 15-17
Generic or follow-on approval	Paragraph IV certification, use-code scope, and regulatory stay

A settlement could permit launch before patent expiration, subject to licensing terms, royalty payments, supply arrangements, or restrictions on the challenged indication. No settlement terms are identified in the supplied record. A license would not necessarily resolve separate patents covering manufacturing, formulations, or other antisense sequences.

How does US 10,870,676 compare with competing DMD patent estates?

US 10,870,676 differs from the patent estates for eteplirsen, golodirsen, and casimersen because those products target exon 51, exon 53, and exon 45 through different antisense sequences and patent families.

The closest comparison is Vyondys 53. Both Viltepso and Vyondys 53 target exon 53, but patent risk turns on the precise oligonucleotide sequence, chemistry, and asserted use claim. A broad commercial description such as "exon-53 skipping" is not enough to determine infringement.

Gene-therapy products such as Elevidys occupy a separate technical and patent category. They deliver a micro-dystrophin transgene through an AAV vector and do not ordinarily practice the antisense sequence limitations in US 10,870,676.

What generic launch scenarios exist?

Same-sequence PMO launch

This is the highest-risk scenario. A product using the claimed target sequence, PMO architecture and intravenous DMD indication could face claims 1, 2, 7, 8, 10, 15, 16 and 18.

Same exon, different target sequence

This scenario reduces literal infringement risk under the supplied claims. It would require a different exon-53 binding site and separate development evidence. Equivalents risk would depend on prosecution history, sequence similarity, function, and the scope surrendered during examination.

Non-PMO antisense chemistry

A modified-ribose or phosphorothioate oligomer may still fall within claims 3 through 6 or 11 through 14. Avoiding the PMO claims does not necessarily avoid the independent claims.

Different modality

A gene therapy, small-molecule dystrophin modulator, or non-antisense treatment would generally fall outside the literal sequence limitations, although it could encounter separate DMD patents.

Key Takeaways

US 10,870,676 is a sequence-specific DMD method patent focused on exon-53 skipping.
Its core protection covers an antisense oligomer complementary to nucleotides 36 through 56 of the disclosed exon-53 sequence.
The patent is commercially relevant to viltolarsen, the active ingredient in Viltepso.
Dependent claims add oligonucleotide, modified-backbone, morpholino, PMO, terminal-group and intravenous-administration limitations.
The patent does not cover every exon-53 therapy or every DMD treatment.
Vyondys 53 is the closest commercial comparator, but infringement requires sequence-level analysis.
Viltepso orphan exclusivity is expected to end around August 2027, while the patent term likely extends into approximately 2033-2034, subject to official term adjustments.
A same-sequence PMO generic would face the highest patent and regulatory risk.
The supplied claims do not independently establish protection for a particular formulation, manufacturing process, dose, or infusion schedule.
Separate patent families must be reviewed for manufacturing, formulation, purification, and product-specific chemistry.

FAQs

Does US 10,870,676 cover Vyondys 53?

Not automatically. Vyondys 53 must be compared with the claimed complementary sequence and the chemical limitations of the asserted claims. Exon-53 targeting alone does not establish infringement.

Can a company design around the patent by changing the PMO terminal group?

Possibly, but changing the terminal group may avoid only claims 9 and 17. The independent claims and broader morpholino claims could remain relevant.

Does the patent cover oral viltolarsen?

The independent claims do not require intravenous administration. Claims 10 and 18 do require intravenous administration, but claims 1 and 2 may remain relevant to another route if the other limitations are met.

Can FDA approve a generic before the patent expires?

FDA approval timing depends on the Orange Book listing, certification, any Paragraph IV litigation, the 30-month stay, orphan-drug exclusivity and other regulatory requirements. Patent expiry alone does not determine the full approval timeline.

Is US 10,870,676 a composition-of-matter patent?

No. Based on the supplied claims, it is primarily a method-of-treatment patent, with a pharmaceutical-composition limitation in claim 2. It does not claim the antisense molecule as a standalone composition independent of use.

References

U.S. Patent and Trademark Office. (n.d.). Patent term adjustment and patent term calculation resources. https://www.uspto.gov
U.S. Food and Drug Administration. (2020). FDA approves targeted treatment for rare Duchenne muscular dystrophy mutation. https://www.fda.gov
U.S. Food and Drug Administration. (n.d.). Orphan drug designation and exclusivity. https://www.fda.gov
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book. https://www.fda.gov
United States Patent and Trademark Office. (2020). U.S. Patent No. 10,870,676: Antisense oligomer for treatment of Duchenne muscular dystrophy. https://patents.google.com/patent/US10870676B2 en

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Nippon Shinyaku	VILTEPSO	viltolarsen	SOLUTION;INTRAVENOUS	212154-001	Aug 12, 2020		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y	Y		TREATMENT OF DUCHENNE MUSCULAR DYSTROPHY (DMD) IN PATIENTS WHO HAVE A CONFIRMED MUTATION OF THE DMD GENE THAT IS AMENABLE TO EXON 53 SKIPPING	⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Japan	2010-196032	Sep 1, 2010

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2011296882	⤷ Start Trial
Canada	2809637	⤷ Start Trial
China	103154245	⤷ Start Trial
Cyprus	1117367	⤷ Start Trial
Cyprus	1122167	⤷ Start Trial
Denmark	2612917	⤷ Start Trial
Denmark	3018211	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 10,870,676

Which drugs does patent 10,870,676 protect, and when does it expire?

Summary for Patent: 10,870,676